Connecting element for hollow sections of different cross-section

ABSTRACT

A connecting element for insertion into the ends of at least two hollow sections of different cross-section, in particular in the case of a middle node ( 20 ) for an instrument panel transverse beam in automobile manufacture is such that a push-fit body ( 22 ) is shape-formed—by way of extrusion of a light weight alloy, plastic or other extrudable material—on a frame ( 30 ) with side walls ( 32 ) extending in the direction of insertion, whereby the push-fit body is of smaller cross-section than the frame and contains lengths of the frame walls ( 32 ). That frame ( 30 ) preferably surrounds the push-fit body ( 22 ) which in turn forms a corner ( 31 ) of the frame ( 22 ). In addition, the frame ( 30 ) may exhibit an integral frame bracket outside one frame side wall whereby the frame bracket walls are aligned with parallel frame walls.

[0001] The invention relates to a connecting element for insertion intothe ends of at least two hollow sections of different cross-section, inparticular a middle node for an instrument panel transverse beam inautomobile manufacture.

[0002] Such connecting elements or middle nodes for hollowsections—possibly of lengths of dish-shaped parts, preferably half-shellshaped parts—in particular hollow sections of rectangular cross-sectionare known in the form of die-cast or shaped sheet parts. Such transversebeams are also known as cockpit carriers and are usually T-shaped with ahollow section on the driver side of the middle node and, on the otherside, another hollow section for the passenger side. A support beam mayalso be present, resulting in a T-shaped transverse beam.

[0003] The known box-shaped middle nodes—with a middle wall and on bothsides an integral rib, in each case forming a cross-section suitable forinsertion purposes—are made by die-casting or by shape-forming andstamping sheet material; these require relatively high tooling costs andusually require very time-consuming post-production processing.Furthermore, the middle nodes for left-hand-drive and right-hand-drivevehicles have to be produced in specially designed tools.

[0004] In view of the above the object of the present invention is toproduce a middle node of the kind mentioned at the start involving lowtooling costs and, thereby, to reduce the cost of post-productionprocessing. In addition, efforts are made to be able to produce themiddle nodes for left-hand-drive and right-hand-drive vehicles using thesame tooling.

[0005] That objective is achieved by way of the invention in that apush-fit body is shape-formed—by way of extrusion of light weight metal,plastic or another extrudable material—in a frame, whereby the push-fitbody is of smaller cross-section than the frame and parts of the frameform parts of the walls of the push-fit body. To that end it has beenfound favourable for the frame to surround the push-fit body and thelatter preferably to be a corner of the frame.

[0006] According to a further detail of the invention an integral framebracket resp. frame hoop may be formed on the outside of one side of theframe, the walls of which frame bracket are aligned with the twoparallel neighbouring frame walls. In order to facilitate the joining ofthis middle node e.g. to a supporting arm projecting out of a vehicletunnel, two sleeves for bolts are provided in opposite lying corners ofthe frame or frame bracket on the frame, said sleeves likewise beingformed in the extrusion process.

[0007] Frames and push-fit bodies may form a compact extruded part whichis delimited by two parallel planes. However, it has been foundfavourable to allow at least the push-fit body on one side to projectout of the frame which penetrates one of the planes. If an integralframe bracket is provided, the frame may project out of one of its sidesand the push-fit body from the other side.

[0008] In all the result is a clever means of manufacturing middle nodesfor the required field of application which meet the set objectives.

[0009] Further advantages, features and details of the invention arerevealed in the following description of preferred exemplifiedembodiments and with the aid of the drawing which shows in

[0010]FIG. 1: a perspective view of a transverse beam with support-ingarm and so called middle node as stiffening element for a private car;

[0011]FIG. 2: an enlarged section from FIG. 1;

[0012]FIG. 3, 4: cross-sections through different versions of thesupport arm;

[0013]FIG. 5: an enlarged perspective view of the middle nodes shown inFIGS. 1 and 2:

[0014]FIG. 6, 8, 10: perspective views of three further versions oftrans-verse beams with middle nodes;

[0015]FIG. 7, 9, 11: enlarged perspective views of the middle nodesshown in FIGS. 6, 8 and 10;

[0016]FIG. 12: a perspective view of another middle node;

[0017]FIG. 13: an end view of the middle node shown in FIG. 12;

[0018]FIG. 14: a front elevation relating to FIGS. 12 and 13;

[0019]FIG. 15, 18, 21: perspective views of three further designs ofmiddle node;

[0020]FIG. 16, 19, 22: front elevations of the middle nodes shown inFIGS. 15, 18, and 21;

[0021]FIG. 17, 20, 23: end views relating to FIGS. 16, 19 and 22.

[0022] A T-shaped transverse beam 10 for installation under theinstrument panel of a private car—not shown here—exhibits a middle node20 as means for connecting a support arm 12, which is vertical wheninstalled, for connection to a support arm 14—at right angles in FIG.1—for the driver side and a support arm 16 for the passenger side. Sucha transverse beam 10 is also known as a cockpit carrier.

[0023] The middle node 20 serves the purpose of providing a transitionfrom the driver-side support arm 14, which is in the form of a hollowsection and approximately quadratic in cross-section, to thepassenger-side support arm 16 which is aligned with the support arm 14.The latter is also a hollow section, the cross-section of which islikewise quadratic and smaller than that of the other support arm 14. Inaddition, the thickness of the four sheet walls 17 of the longer supportarm 16 is less than the thickness of the walls 15 of the support arm 14for the driver side. Also the middle node 20 should accommodate thistransition in wall thickness onto which the support arms 14, 16 arepushed in direction x.

[0024] The support arm 12—serving as support for the vehicle tunnelwhich is not shown here—features, as shown in FIG. 3, a narrow, open,rectangular, shell-like cross-section and, as 12 _(d) in FIG. 4, adouble shell-like cross-section and is fitted close to its upper edge 13with openings 18 for bolts or other connecting elements.

[0025] The middle node 20 shown in FIGS. 1, 2 and 5 is in one piece,manufactured by extrusion of a light metal alloy, and exhibits anapproximately quadratic push-fit body 22 of height a at the side andbreadth b, the outer contour of which corresponds to the inner contourof the narrower support arm 16, with little play; the faces of its walls24 are oriented in the direction of displacement or insertion x. Thepush-fit body 22 is integrated in a likewise quadratic frame 30 of abouthalf the breadth b₁, and about double the height e such that thepush-fit body 22 forms one frame corner 31 and two of the strip-shapedsides 32 run into the aligned body walls 24, whereby one of the walledges 26—the rear edge in FIG. 5—coincides with the edge 34 of therelated frame side 32 i.e. the push-fit body 22 projects out of one sideof the frame 30 by a distance f; the latter corresponds approximately tothe breadth b₁.

[0026] Provided on the outside, at the free inner corner 28 of thepush-fit body 22, is an integral diagonal strip 36 of breadth b₁ whichruns to the above mentioned neighbouring, diagonally opposite corner 31_(a) of the push-fit body 22 where an intervening sleeve 38 for a boltis situated. The corners 31, 31 _(a) are rounded. A second sleeve 38 fora bolt is provided in the other corner 31 _(a), parallel to and oppositethe sleeve 38 connected to the diagonal strip 36; in the installedposition both sleeves 38 are aligned with the openings 18 at the uppercorners 13 of the support arm 12, 12 _(d) to accommodate bolts orconnecting elements along with the openings 12, 12 _(a).

[0027] In the case of the middle node 20 _(a) in FIGS. 6 and 7 thebreadth b1 of side 32 is equal to approximately one third of the breadthb of the wall 24. Here, the integral diagonal strip 36 is situateddirectly in the corner 31 _(a); the sleeves 38 for bolts are situated incorners 41 of an additional integral U-like frame bracket 40 of height hto the lower side 32 _(t) of the frame. Both parallel side walls 42 ofthe U-like frame bracket 40 are integrally attached to its base strip 44and are in line with the side wall strips 32 of the frame 30 and itsedge—in FIG. 7—front edge 46 is in line with the front edge 34. Thebreadth b₁ of the frame strip 32 corresponds approximately to double thebreadth b₂ of the frame bracket 40.

[0028] The breadth b of the push-fit body 32 _(b) in frame 30 in FIGS. 8and 9 is the same as its breadth b1; otherwise, this middle node 20 _(b)is the same shape as the middle node 20 described above. Middle node 20_(c) (FIGS. 10, 11) corresponds essentially to middle node 20 _(b) inFIGS. 8 and 9 with an additional frame bracket 40 in the design shown inFIG. 7.

[0029] Middle node 20 _(d) in FIGS. 12 to 14, of overall height i ofapprox. 115 mm and a transverse dimension e₁ of approx. 70 mm, exhibitsa wall thickness t of 4 mm.

[0030] Both a corner 31 _(b) of the frame 30 and the diagonal corner 41b of the frame bracket 40 form an angle w of 45°. The same holds for acorner region 23 of push-fit body 22 _(d) . This is integrally formed ona diagonal strip 36 which here is continuous and makes an angle w₁ of45° with the side wall 32. The overall length n of the middle node 20_(d) corresponds approximately with its side wall e of approx. 100 mm,the outer height a₁, of the push-fit body 22 _(a), here 55 mm, itsbreadth a₂ 40 mm.

[0031] As illustrated in particular in FIG. 14, frame 30 projects on oneside beyond the outer edge 46 of the frame bracket 40—or beyond theplanes E, E₁ defined by this—by a distance g of about 24 mm, and on theother side the push-fit body 22 _(d) by a distance k of 36 mm.

[0032] The middle node 20 _(e) shown in FIGS. 15 to 17 correspondsapproximately to middle node 20 _(d) without frame bracket 40. Themiddle node 20 _(f), shown in FIGS. 18 to 20, is approximately the sameas the previously described middle node 20 _(e), whereby, however, theessentially rectangular push-fit body 22 _(f)—as viewed incross-section—does not project out, its breadth corresponds to thebreadth b₁ of frame 30 _(a).

[0033] In FIGS. 21 to 23 the frame bracket 40 is again integrally formedon the frame 30 _(a) described in FIGS. 18-20, from which a part of theframe 30 _(a) containing the push-fit body 22 _(a) projects out adistance g.

1. Connecting element for insertion into the ends of at least two hollowsections of different cross-section, in particular middle nodes for aninstrument panel transverse beam in automobile manufacture,characterised in that, a push-fit body (22, 22 _(a) to 22 _(f)) isshape-formed by way of extrusion on a frame (30, 30 _(a)) with sidewalls (32) extending in the direction x of insertion, whereby thepush-fit body is of smaller cross-section than the frame and containslengths of the frame walls.
 2. Connecting element according to claim 1,characterised in that the frame (30, 30 _(a)) surrounds the push-fitbody (22, 22 _(a) to 22 _(f)).
 3. Connecting element according to claim1 or 2, characterised in that the push-fit body ((22, 22 _(a) to 22_(f)) forms a corner (31) of the frame (30, 30 _(a)).
 4. Connectingelement according to one of the claims 1 to 3, characterised in that aframe bracket (40) is formed onto the frame (30, 30 _(a)) on the outsideof one side wall (32 _(f)).
 5. Connecting element according to claim 4,characterised in that the frame bracket arms (42) on the frame (30, 30_(a)) are aligned with parallel side walls of the frame.
 6. Connectingelement according to one of the claims 1 to 5, characterised in that asleeve (38) for a bolt is provided, in particular integrallyshape-formed, at two opposite lying corners (31 _(a) and 41) within theframe (30, 30 _(a)) or in the frame bracket (40).
 7. Connecting elementaccording to one of the claims 1 to 5, characterised in that thepush-fit body (22, 22 a, 22 _(d)) projects out of one side of the frame(30, 30 _(a)) in the direction of insertion (x).
 8. Connecting elementaccording to one of the claims 1 to 7, characterised in that the frame(30, 30 _(a)) projects on one side in the direction of insertion beyonda plane (E) defined by an outer edge (46) of the frame bracket (40). 9.Connecting element according to claim 8, characterised in that on theother side of the frame bracket (40) the push-fit body (22 _(d))projects beyond a plane (E) defined by its other outer edge (46). 10.Connecting element according to at least one of the above claims,characterised by way of at least one of the features revealed in thedrawing and/or description.
 11. Connecting element according to at leastone of the above claims, characterised by way of a combination of atleast two of the features revealed in the drawing and/or description.